Supramolecular Interactions-Assisted Polymorphism and Unique Mechanofluorochromism in 9,10-Bis((E)-4-(trifluoromethyl)styryl)anthracene.

A fluorinated distyrylanthracene (DSA) derivative, 9, 10-bis((E)-4-(trifluoromethyl)styryl)anthracene abbreviated as 4FDSA with two crystalline polymorphs (4FDSA-G (green emission) and 4FDSA-O (orange emission)), showing remarkable aggregation-induced enhanced emission and mechanofluorochromic characteristics, was developed. One of the polymorphs in its crystalline arrangement exhibits the hardly seen F…F interactions. It questions the conventional belief of the non-polarisable nature of fluorine atoms in forming the halogen bond.